GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/h264_mp4toannexb_bsf.c Lines: 106 149 71.1 %
Date: 2020-01-28 04:56:05 Branches: 66 114 57.9 %

Line Branch Exec Source
1
/*
2
 * H.264 MP4 to Annex B byte stream format filter
3
 * Copyright (c) 2007 Benoit Fouet <benoit.fouet@free.fr>
4
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
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 * FFmpeg is distributed in the hope that it will be useful,
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
16
 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21
22
#include <string.h>
23
24
#include "libavutil/avassert.h"
25
#include "libavutil/intreadwrite.h"
26
#include "libavutil/mem.h"
27
28
#include "avcodec.h"
29
#include "bsf.h"
30
#include "h264.h"
31
32
typedef struct H264BSFContext {
33
    int32_t  sps_offset;
34
    int32_t  pps_offset;
35
    uint8_t  length_size;
36
    uint8_t  new_idr;
37
    uint8_t  idr_sps_seen;
38
    uint8_t  idr_pps_seen;
39
    int      extradata_parsed;
40
} H264BSFContext;
41
42
1740
static int alloc_and_copy(AVPacket *out,
43
                          const uint8_t *sps_pps, uint32_t sps_pps_size,
44
                          const uint8_t *in, uint32_t in_size, int ps)
45
{
46
1740
    uint32_t offset         = out->size;
47

1740
    uint8_t start_code_size = offset == 0 || ps ? 4 : 3;
48
    int err;
49
50
1740
    err = av_grow_packet(out, sps_pps_size + in_size + start_code_size);
51
1740
    if (err < 0)
52
        return err;
53
54
1740
    if (sps_pps)
55
14
        memcpy(out->data + offset, sps_pps, sps_pps_size);
56
1740
    memcpy(out->data + sps_pps_size + start_code_size + offset, in, in_size);
57
1740
    if (start_code_size == 4) {
58
412
        AV_WB32(out->data + offset + sps_pps_size, 1);
59
    } else {
60
1328
        (out->data + offset + sps_pps_size)[0] =
61
1328
        (out->data + offset + sps_pps_size)[1] = 0;
62
1328
        (out->data + offset + sps_pps_size)[2] = 1;
63
    }
64
65
1740
    return 0;
66
}
67
68
5
static int h264_extradata_to_annexb(AVBSFContext *ctx, const int padding)
69
{
70
5
    H264BSFContext *s = ctx->priv_data;
71
    uint16_t unit_size;
72
5
    uint32_t total_size                 = 0;
73
5
    uint8_t *out                        = NULL, unit_nb, sps_done = 0,
74
5
             sps_seen                   = 0, pps_seen = 0;
75
5
    const uint8_t *extradata            = ctx->par_in->extradata + 4;
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    static const uint8_t nalu_header[4] = { 0, 0, 0, 1 };
77
5
    int length_size = (*extradata++ & 0x3) + 1; // retrieve length coded size
78
79
5
    s->sps_offset = s->pps_offset = -1;
80
81
    /* retrieve sps and pps unit(s) */
82
5
    unit_nb = *extradata++ & 0x1f; /* number of sps unit(s) */
83
5
    if (!unit_nb) {
84
        goto pps;
85
    } else {
86
5
        s->sps_offset = 0;
87
5
        sps_seen = 1;
88
    }
89
90
15
    while (unit_nb--) {
91
        int err;
92
93
10
        unit_size   = AV_RB16(extradata);
94
10
        total_size += unit_size + 4;
95
        av_assert1(total_size <= INT_MAX - padding);
96
10
        if (extradata + 2 + unit_size > ctx->par_in->extradata + ctx->par_in->extradata_size) {
97
            av_log(ctx, AV_LOG_ERROR, "Packet header is not contained in global extradata, "
98
                   "corrupted stream or invalid MP4/AVCC bitstream\n");
99
            av_free(out);
100
            return AVERROR(EINVAL);
101
        }
102
10
        if ((err = av_reallocp(&out, total_size + padding)) < 0)
103
            return err;
104
10
        memcpy(out + total_size - unit_size - 4, nalu_header, 4);
105
10
        memcpy(out + total_size - unit_size, extradata + 2, unit_size);
106
10
        extradata += 2 + unit_size;
107
10
pps:
108

10
        if (!unit_nb && !sps_done++) {
109
5
            unit_nb = *extradata++; /* number of pps unit(s) */
110
5
            if (unit_nb) {
111
5
                s->pps_offset = total_size;
112
5
                pps_seen = 1;
113
            }
114
        }
115
    }
116
117
5
    if (out)
118
5
        memset(out + total_size, 0, padding);
119
120
5
    if (!sps_seen)
121
        av_log(ctx, AV_LOG_WARNING,
122
               "Warning: SPS NALU missing or invalid. "
123
               "The resulting stream may not play.\n");
124
125
5
    if (!pps_seen)
126
        av_log(ctx, AV_LOG_WARNING,
127
               "Warning: PPS NALU missing or invalid. "
128
               "The resulting stream may not play.\n");
129
130
5
    av_freep(&ctx->par_out->extradata);
131
5
    ctx->par_out->extradata      = out;
132
5
    ctx->par_out->extradata_size = total_size;
133
134
5
    return length_size;
135
}
136
137
5
static int h264_mp4toannexb_init(AVBSFContext *ctx)
138
{
139
5
    H264BSFContext *s = ctx->priv_data;
140
5
    int extra_size = ctx->par_in->extradata_size;
141
    int ret;
142
143
    /* retrieve sps and pps NAL units from extradata */
144

5
    if (!extra_size                                               ||
145

5
        (extra_size >= 3 && AV_RB24(ctx->par_in->extradata) == 1) ||
146
5
        (extra_size >= 4 && AV_RB32(ctx->par_in->extradata) == 1)) {
147
        av_log(ctx, AV_LOG_VERBOSE,
148
               "The input looks like it is Annex B already\n");
149
5
    } else if (extra_size >= 6) {
150
5
        ret = h264_extradata_to_annexb(ctx, AV_INPUT_BUFFER_PADDING_SIZE);
151
5
        if (ret < 0)
152
            return ret;
153
154
5
        s->length_size      = ret;
155
5
        s->new_idr          = 1;
156
5
        s->idr_sps_seen     = 0;
157
5
        s->idr_pps_seen     = 0;
158
5
        s->extradata_parsed = 1;
159
    } else {
160
        av_log(ctx, AV_LOG_ERROR, "Invalid extradata size: %d\n", extra_size);
161
        return AVERROR_INVALIDDATA;
162
    }
163
164
5
    return 0;
165
}
166
167
530
static int h264_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out)
168
{
169
530
    H264BSFContext *s = ctx->priv_data;
170
171
    AVPacket *in;
172
    uint8_t unit_type;
173
    int32_t nal_size;
174
530
    uint32_t cumul_size    = 0;
175
    const uint8_t *buf;
176
    const uint8_t *buf_end;
177
    int            buf_size;
178
530
    int ret = 0, i;
179
180
530
    ret = ff_bsf_get_packet(ctx, &in);
181
530
    if (ret < 0)
182
132
        return ret;
183
184
    /* nothing to filter */
185
398
    if (!s->extradata_parsed) {
186
        av_packet_move_ref(out, in);
187
        av_packet_free(&in);
188
        return 0;
189
    }
190
191
398
    buf      = in->data;
192
398
    buf_size = in->size;
193
398
    buf_end  = in->data + in->size;
194
195
    do {
196
1741
        ret= AVERROR(EINVAL);
197
1741
        if (buf + s->length_size > buf_end)
198
            goto fail;
199
200
8705
        for (nal_size = 0, i = 0; i<s->length_size; i++)
201
6964
            nal_size = (nal_size << 8) | buf[i];
202
203
1741
        buf += s->length_size;
204
1741
        unit_type = *buf & 0x1f;
205
206

1741
        if (nal_size > buf_end - buf || nal_size < 0)
207
1
            goto fail;
208
209
1740
        if (unit_type == H264_NAL_SPS)
210
            s->idr_sps_seen = s->new_idr = 1;
211
1740
        else if (unit_type == H264_NAL_PPS) {
212
            s->idr_pps_seen = s->new_idr = 1;
213
            /* if SPS has not been seen yet, prepend the AVCC one to PPS */
214
            if (!s->idr_sps_seen) {
215
                if (s->sps_offset == -1)
216
                    av_log(ctx, AV_LOG_WARNING, "SPS not present in the stream, nor in AVCC, stream may be unreadable\n");
217
                else {
218
                    if ((ret = alloc_and_copy(out,
219
                                         ctx->par_out->extradata + s->sps_offset,
220
                                         s->pps_offset != -1 ? s->pps_offset : ctx->par_out->extradata_size - s->sps_offset,
221
                                         buf, nal_size, 1)) < 0)
222
                        goto fail;
223
                    s->idr_sps_seen = 1;
224
                    goto next_nal;
225
                }
226
            }
227
        }
228
229
        /* if this is a new IDR picture following an IDR picture, reset the idr flag.
230
         * Just check first_mb_in_slice to be 0 as this is the simplest solution.
231
         * This could be checking idr_pic_id instead, but would complexify the parsing. */
232

1740
        if (!s->new_idr && unit_type == H264_NAL_IDR_SLICE && (buf[1] & 0x80))
233
            s->new_idr = 1;
234
235
        /* prepend only to the first type 5 NAL unit of an IDR picture, if no sps/pps are already present */
236


1740
        if (s->new_idr && unit_type == H264_NAL_IDR_SLICE && !s->idr_sps_seen && !s->idr_pps_seen) {
237
14
            if ((ret=alloc_and_copy(out,
238
14
                               ctx->par_out->extradata, ctx->par_out->extradata_size,
239
                               buf, nal_size, 1)) < 0)
240
                goto fail;
241
14
            s->new_idr = 0;
242
        /* if only SPS has been seen, also insert PPS */
243


1726
        } else if (s->new_idr && unit_type == H264_NAL_IDR_SLICE && s->idr_sps_seen && !s->idr_pps_seen) {
244
            if (s->pps_offset == -1) {
245
                av_log(ctx, AV_LOG_WARNING, "PPS not present in the stream, nor in AVCC, stream may be unreadable\n");
246
                if ((ret = alloc_and_copy(out, NULL, 0, buf, nal_size, 0)) < 0)
247
                    goto fail;
248
            } else if ((ret = alloc_and_copy(out,
249
                                        ctx->par_out->extradata + s->pps_offset, ctx->par_out->extradata_size - s->pps_offset,
250
                                        buf, nal_size, 1)) < 0)
251
                goto fail;
252
        } else {
253

1726
            if ((ret=alloc_and_copy(out, NULL, 0, buf, nal_size, unit_type == H264_NAL_SPS || unit_type == H264_NAL_PPS)) < 0)
254
                goto fail;
255

1726
            if (!s->new_idr && unit_type == H264_NAL_SLICE) {
256
12
                s->new_idr = 1;
257
12
                s->idr_sps_seen = 0;
258
12
                s->idr_pps_seen = 0;
259
            }
260
        }
261
262
1714
next_nal:
263
1740
        buf        += nal_size;
264
1740
        cumul_size += nal_size + s->length_size;
265
1740
    } while (cumul_size < buf_size);
266
267
397
    ret = av_packet_copy_props(out, in);
268
397
    if (ret < 0)
269
        goto fail;
270
271
397
fail:
272
398
    if (ret < 0)
273
1
        av_packet_unref(out);
274
398
    av_packet_free(&in);
275
276
398
    return ret;
277
}
278
279
static void h264_mp4toannexb_flush(AVBSFContext *ctx)
280
{
281
    H264BSFContext *s = ctx->priv_data;
282
283
    s->idr_sps_seen = 0;
284
    s->idr_pps_seen = 0;
285
    s->new_idr      = s->extradata_parsed;
286
}
287
288
static const enum AVCodecID codec_ids[] = {
289
    AV_CODEC_ID_H264, AV_CODEC_ID_NONE,
290
};
291
292
const AVBitStreamFilter ff_h264_mp4toannexb_bsf = {
293
    .name           = "h264_mp4toannexb",
294
    .priv_data_size = sizeof(H264BSFContext),
295
    .init           = h264_mp4toannexb_init,
296
    .filter         = h264_mp4toannexb_filter,
297
    .flush          = h264_mp4toannexb_flush,
298
    .codec_ids      = codec_ids,
299
};